Shredder for woven fabrics



R. E. HOWE SHREDDER FOR WOVEN FABRICS Nov. 26, 1940;

Filed July 14, 1939 FIE.1.

I INVENTOR.

Patented Nov. 26, 1940 UNITED STATES PATENT OFFICE 2,222,799 I SHREDDER FOR WOVEN FABRICS Ralph E. Howe, Troy, N. H.

Application July 14, 1989, Serial No. 284,489

2 Claims.

This invention relates to machines for separating or shredding cloth, or material such as burlap, woven of relatively large threads made from twisted fibers, from three to ten inches long, of jute, ramie, sisal, hemp or similar stock. Such cloth is loosely woven together and, as ordinarily received, contains a great deal of dirt. This machine is for the purpose of shredding or pulling apart such stock so as to prepare it for a picker. It is not useful in picking wool or. cotton fibers or in turning relatively fine cotton, wool, worsted, rayon or silk, woven cloth or knit material into stock suitable for carding.

This machine is to shred or change such cloth into separate fibers and twisted threads. of such a character that, particularly when somewhat cleaner, it can be passed through a regular standard picker.

The principal feature'is the shape of the teeth on the main fast moving drum which come in contact with one or more thicknesses of the woven stock as it is carried forward over the rounded edge of a shredding bar plate by a feed roller.

If the free ends of the teeth on such a drum rake forward too much from radial planes in the direction in which the surface is traveling, or if the points of the tips of the free ends are too sharp, they catch the stock and there is a pulling and wearing action back from the points of the teeth which eventually cuts through the tip near the point with the result that this end gets into the work and the tooth must be replaced.

I have found that if the curve or forward rake of the free end of the tooth is relatively slight and if the width and the height of the tip are both greater than the interstices, or spaces between the parallel warp threads and the adjoining parallel filling threads, this wearing is prevented and the stock delivered by this machine is in better condition for the picker.

I am aware that various kinds of stock have been treated by cotton gins, beater arms working on stock as it passes through feed rolls, straight picker pins, pickers with curved teeth, breasts with garnet wire, cards with garnet wire and card clothing and that workers and strippers have been used on cards and breasts all for treatment for different kinds of stock in the different stages of the procedure, but this machine is for treating material, such as closely woven, dirty jute, in such a Way that it can be easily cleaned and passed along to the picker.

By raking forward is meant that the free part of the teeth or pins point in the same direction in which they are moving and by raking backward is meant that they point in the opposite direction.

In the drawing, Fig. l is a side elevation, partly in section, of an entire shredder.

Fig. 2 is a side elevation of the old type tooth.

Fig. 3 is a side elevation of my new tooth.

Fig. dis a top view of Fig. 3.

Fig. 5 is a much exaggerated diagrammatic view of a plurality of thicknesses of the material being operated on, the point of the tooth being indicated in dotted lines.

Fig. 6 is 'a plan view of Fig. 2.

Fig. 7 is a plan view of Fig. 3.

In the drawing, M is the frame of the machine and N represents one of two carrier drums for a feed apron O on which the stock W, W to be treated is placed. This stock consists of woven material and is usually placed upon the apron O in such a manner that the warp and filling threads are crossed in all directions, as shown in Fig. 5.

A is a smooth feed roll and B is what is known as a cockspur roll having teeth, such as l, which rake backward in the direction opposite from the direction in which it rotates.

P represents a plate bed or what is known as a shredding bar having a curved surface which is substantially concentric with the surface of a feed roller C, and L is a plate attached to bar P in any suitable manner and ending at the top in a blunt edge 2 which preferably is of hardened steel.

The feed roller C is teeth 3 and preferably travels at a somewhat greater surface speed than the feed rolls A and B so that there is a slight stretching or drawing of the material between them. These feeding devices carry the material W along and up over the edge 2 where it is treated by the teeth H, a plurality of which extend radially outwardly from the drum E which is carried by a shaft 4 substantially on a level with the edge 2.

Each tooth I-I includes a shank 5 which is usually. round and is attached to a lag 6 in any convenient way, as by a bolt or pin 1.

S is the forwardly raking free end of each tooth which preferably tapers to some extent and ends at 9 in a rounded tip. This rounded tip 9, as shown in detail in Figs. 3, 4, 5 and 7, is of a provided with pins or greater width and a greater height than the interstices between adjoining warp threads 20, 20 and adjoining filling threads 2|, 2! of the cloth W to be operated on.

The surface speed of the rolls A and B is approximately eighteen feet per minute, of roller C eighteen and one-half feet per minute and of the tips 9, 9 of the teeth H, H on the drum E 6600 feet per minute.

The distance from the tips 9 of the teeth from the edge 2 of the plate L may be about oneeighth of an inch. The plate P and bar or edge L and roll A do not change their position but the rolls B and C may be provided with springs, such as 10 and I I, so that they can rise to permit the passage of lumps, etc.

I claim:

1. In a shredder for woven jute and similar material, the combination with feeding devices, including a feed plate having a blunt edge; of a drum with a plurality of teeth extending radially out from its curved surface, each tooth having a round shank and a forwardly raking tapering free end which ends in a rounded tip of greater width and height than the interstices between the warp and filling threads to be operated on.

2. In a shredder for woven jute and similar material, the combination with feeding devices; of a drum with a plurality of teeth extending radially out from its curved surface, each tooth having a shank and a forwardly raking free end which ends in a tip of greater width'a'nd height than the interstices between the warp and filling threads to be operated on.

RALPH E. HOWE. 

